Rex Jones has spent his entire athletic training career in the Astros organization. He earned his call to the big leagues in 1994 after spending 16 years in the club's minor league system. From 1988-93, he was the organization's director of minor league athletic trainers.

Jones started his career in 1978 with the Class A Daytona Beach club, while working toward a bachelor's degree in physical education from Missouri State University. He was head trainer for the Double A Columbus Astros from 1979-82 before being promoted to the Triple A Tucson Toros in 1983.

Jones earned his master's degree from Central Missouri State. He is a certified member of the National Athletic Trainers Association and is licensed as an athletic trainer in the state of Texas. Additionally, Jones is a member of the Southwest Athletic Trainers Association, and the Greater Houston Athletic Trainers Society. In 2004, he served as a trainer for the National League All-Star team at Minute Maid Park.
He and his wife, Annie, have three children, Megan, Laura and Jeremiah.